//
//  IBNumberEditText.swift
//  MTP2_iOS
//
//  Created by Handy_Cao on 2018/11/10.
//  Copyright © 2018 Muchinfo. All rights reserved.
//

import UIKit

/// 输入框按钮类型
///
/// - Add: 加
/// - Subtract: 减
enum NumberInputViewButtonType {
    case Add
    case Subtract
}

@IBDesignable
class IBNumberEditText: UIView {
    
    // MARK: - 属性列表
    /// 减号
    @IBOutlet weak var minusBtn: IBButton!
    /// 加号
    @IBOutlet weak var addBtn: IBButton!
    /// 输入框
    @IBOutlet weak var numberField: IBTextField!
    /// 定义container为DemoView的子view, 以便更方便的封装xib
    @IBOutlet weak var containerView: UIView!
    
    /// 小数位，如果需要则设置
    var decimalPlace: Int?
    /// 增量(默认值为1)
    var incrementIntNum = 1
    var incrementDoubleNum: Double = 1
    /// 最大值
    var maxIntNum = Int.max
    var maxDoubleNum = Double(Int.max)
    /// 最小值
    var minIntNum = 0
    var minDoubleNum = 0.0
    /// 是否循环
    var isWarp = false
    /// 不允许交互
    override var isUserInteractionEnabled: Bool {
        didSet {
            addBtn.layer.borderColor = UIColorFromHex(rgbValue: isUserInteractionEnabled ? 0x333333 : 0xcccccc).cgColor
            minusBtn.layer.borderColor = UIColorFromHex(rgbValue: isUserInteractionEnabled ? 0x333333 : 0xcccccc).cgColor
            numberField.textColor = UIColorFromHex(rgbValue: isUserInteractionEnabled ? 0x3384F3 : 0x999999)
        }
    }
    /// 代理
    weak var delegate: IBNumberEditTextDelegate?
    /// 需要的值类型 1: Int   2: Double
    var valueType = 1 {
        didSet {
            switch valueType {
            case 1:
                numberField.keyboardType = .numberPad
            default:
                numberField.keyboardType = .decimalPad
            }
        }
    }
    
    /// 当前Int值
    var currentIntNumbers: Int {
        get {
            return Int(numberField.text!) ?? 0
        }
        set {
            if newValue > maxIntNum {
                numberField.text = String(maxIntNum)
            } else {
                numberField.text = String(newValue)
            }
            delegate?.IBNumberEditText(textField: numberField)
        }
    }
    
    /// 当前Double值
    var currentDoubleNumbers: Double {
        get {
            if let decimalPlace = decimalPlace {
                /// FIXME: - 暂时用于解决浮点数计算失真问题
                return Double(String(format: "%.\(decimalPlace)f", Double(numberField.text!) ?? 0)) ?? 0
            } else {
                return Double(numberField.text!) ?? 0
            }
        }
        set {
            if let decimalPlace = decimalPlace {
                if Double(Int(newValue)) == newValue {
                    numberField.text = newValue.toString(reserve: decimalPlace)
                } else {
                    numberField.text = String(format: "%.\(decimalPlace)f", newValue)
                }
            } else {
                if Double(Int(newValue)) == newValue {
                    numberField.text = newValue.toString(reserve: decimalPlace ?? 0)
                } else {
                    numberField.text = newValue.toString(reserve: decimalPlace ?? 0)
                }
            }
            delegate?.IBNumberEditText(textField: numberField)
        }
    }
    
    // MARK: - 生命周期
    override init(frame: CGRect) {
        super.init(frame: frame)
        initViewFromNib()
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        initViewFromNib()
    }
    
    private func initViewFromNib() {
        /// 需要这句代码，不能直接写UINib(nibName: "MyView", bundle: nil)，不然不能在storyboard中显示
        let bundle = Bundle.init(for: self.classForCoder)
        let nib = UINib(nibName: "NumberEditText", bundle: bundle)
        containerView = nib.instantiate(withOwner: self, options: nil)[0] as? UIView
        containerView.frame = bounds
        addSubview(containerView)
    }
    
    override func awakeFromNib() {
        NotificationCenter.default.addObserver(self, selector: #selector(valueChanged), name: UITextField.textDidChangeNotification, object: numberField)
    }
    
    @objc fileprivate func valueChanged() {
        delegate?.IBNumberEditText(textField: numberField)
    }
    
    deinit {
        NotificationCenter.default.removeObserver(self)
    }
    
    // MARK: - 交互相关
    @IBAction func onButtonPressed(_ sender: IBButton) {
        switch sender {
        case addBtn:
            if valueType == 1 {
                if currentIntNumbers < maxIntNum {
                    currentIntNumbers += incrementIntNum
                } else if isWarp {
                    currentIntNumbers = minIntNum
                }
            } else {
                if currentDoubleNumbers < maxDoubleNum {
                    currentDoubleNumbers += incrementDoubleNum
                } else if isWarp {
                    currentDoubleNumbers = minDoubleNum
                }
            }
            
            /// 出发代理
            guard let delegate = self.delegate else { return }
            delegate.numberInputView(self, .Add)
            
        case minusBtn:
            if valueType == 1 {
                if currentIntNumbers > minIntNum {
                    currentIntNumbers -= incrementIntNum
                } else if isWarp {
                    currentIntNumbers = maxIntNum
                }
            } else {
                if currentDoubleNumbers > minDoubleNum {
                    currentDoubleNumbers -= incrementDoubleNum
                } else if isWarp {
                    currentDoubleNumbers = maxDoubleNum
                }
            }
            
            /// 出发代理
            guard let delegate = self.delegate else { return }
            delegate.numberInputView(self, .Subtract)
            
        default:
            break
        }
        
        /// 通知值变化
        delegate?.IBNumberEditText(textField: numberField)
    }
    
    /// 是否置为不可用
    var isDisabled = false {
        didSet {
            self.isUserInteractionEnabled = !isDisabled
            addBtn.isEnabled = !isDisabled
            minusBtn.isEnabled = !isDisabled
        }
    }
}

extension IBNumberEditText: UITextFieldDelegate {
    func textFieldDidBeginEditing(_ textField: UITextField) {
        if Double(textField.text!) == 0 {
            textField.text = ""
        }
    }
    
    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        
        /// 解决删除按钮失效问题
        if (range.length == 1 && string.count == 0) {
            
            return true
        }
        
        if let decimalPlace = decimalPlace,
            let num = textField.text?.split(separator: ".").compactMap(String.init),
            num.count == 2, num[1].count == decimalPlace {
            
            return false
        }
        
        return true
    }
    
    func textFieldDidEndEditing(_ textField: UITextField) {
        /// 类型为整数型
        if valueType == 1 {
            self.currentIntNumbers = Int(self.currentIntNumbers/self.incrementIntNum)*Int(self.incrementIntNum)
        }
        
        /// numberInputViewDidEndEditing
        delegate?.numberInputViewDidEndEditing(self)
    }
}

protocol IBNumberEditTextDelegate: class {
    /// valueChanged 触发
    ///
    /// - Parameter textField: 值变化的输入框
    func IBNumberEditText(textField: UITextField)
    
    /// 按钮点击出发
    ///
    /// - Parameters:
    ///   - buttonType: 按钮类型
    func numberInputView(_ numberInputView: IBNumberEditText, _ buttonType: NumberInputViewButtonType)
    
    /// numberInputViewDidEndEditing
    /// - Parameter numberInputView: numberInputView
    func numberInputViewDidEndEditing(_ numberInputView: IBNumberEditText)
}